Aim. To detect the expression of
dual oxidase (DUOX) 2 in
Barrett esophagus,
gastric cancer, and
colorectal cancer (CRC). Materials and Methods. The endoscopic biopsies were collected from patients with
Barrett esophagus, while the curative resection tissues were obtained from patients with
gastric cancer, CRC, or hepatic
carcinoma. The
DUOX2 protein and
mRNA levels were detected with immunohistochemistry (IHC) and real-time quantitative PCR (qPCR). The correlation of
DUOX2 expression with clinicopathological parameters of
tumors was identified. Results. Low levels of
DUOX2 mRNA were detected in
Barrett esophagus and the adjacent normal tissues, and there was no difference between these two groups.
DUOX2 protein was found in
Barrett esophagus and undetectable in the normal epithelium. The
DUOX2 mRNA and
protein levels in the
gastric cancer and CRC were increased compared to the adjacent nonmalignant tissues. The elevated
DUOX2 in the
gastric cancer was significantly associated with smoking history. In CRC tissues, the
DUOX2 protein expression level in stages II-IV was significantly higher than that in stage I. In both hepatic
carcinoma and the adjacent nonmalignant tissue, the
DUOX2 was virtually undetectable. Conclusion.
DUOX2 in
Barrett esophagus,
gastric cancer, and CRC may be involved in the
tumorigenesis of these tissues.